The Tissue Resource Core of the Robert H. Lurie Comprehensive Cancer Center's Specialized Program of Research Excellence (SPORE) in breast cancer has two dedicated breast cancer treatment centers, Northwestern Memorial Hospital (NMH) and Evanston Northwestern Healthcare (ENH), dedicated to the collection, storage and distribution of human breast cancer for research. Because our institutions see large numbers of new breast cancer patients each year for surgical excision (>1100), our access to patient derived tissues for research is high (containing 12,000 archived cases and 450 fresh frozen samples to date), houses the national Pathology Coordinating Office (solid tumor tissue bank) for ECOG, and has participated with the UCSF and UNC SPORE programs as a sub- contracting institution. The NMH facility also has significant expertise in tumor banking through the Cancer Center's Research Histology/Tissue Procurement shared resource. This core will facilitate both the collection of fixed embedded and fresh frozen tissues as well as the acquisition and database storage of essential pathologic and clinical information needed for conducting translational research. This resource will benefit not only to the SPORE investigators, it will facilitate research activities of other scientists within and outside the parent institution. With time and accrual, we will be willing to participate in NCI-supported tissue networks so that the benefits of this resource are beyond our institution. This process will be supervised by a Tissue Review and Disbursement Committee, (including physicians and pathologists), and SPORE Executive Committee and reviews by the individual Institutional Review Boards (IRBs) on an annual basis.